The present invention relates to liquid heating systems; more particularly, the present invention relates to a liquid heating system for use with a swimming pool or the like.
The need for heating swimming pool water is recognized in both cold and warm climates. In warm climates the use of a swimming pool may be limited to only those months where the ambient temperature is sufficient to warm the swimming pool water to a comfortable level. In colder climates, swimming pool water must be continually heated in order to provide comfortable aquatic recreation.
In other situations there may be a need for warmed water. Such situations may include water used for plants in greenhouses or water used when raising animals. In still other situations, warmed water may be needed for washing or other industrial applications. (Because a swimming pool is exemplary of these needs, it will be used as the basis of the description which follows.)
One solution to the problem of heating swimming pool water has been the use of gas fired heaters. Such gas fired heaters are expensive to obtain and install; and, given the rising cost of natural gas, increasingly costly to operate. Consequently, the use of gas fired swimming pool water heaters has been somewhat limited.
The use of warmed refrigerant in a home air conditioning system to raise the temperature of swimming pool water was initially proposed in U.S. Pat. No. 3,498,072 to Stiefel. Therein, the substitution of a swimming pool water cooled condensor for an ambient air condensor was initially proposed. After that initial disclosure, other inventors devised more complex systems for automatic control of the flow of heated refrigerant and swimming pool water temperatures. Exemplary of such efforts are U.S. Pat. No. 3,926,008 to Webber, U.S. Pat. No. 4,019,338 to Poteet, U.S. Pat. No. 4,279,128 to Leniger and U.S. Pat. No. 4,557,116 to Kittler.
Despite the teachings of others on using waste heat from the warmed refrigerant in an air conditioning system to warm swimming pool water and the clear economic benefit as illustrated in U.S. Pat. No. 3,498,072 to Stiefel, no low cost, simple, commercially successful swimming pool water heating system has been produced. One of the reasons for this failure may be that none of the aforementioned attempts to produce a swimming pool water heating system has addressed the problem of providing a flow of water in sufficient quantity and at a sufficient velocity to obtain an effective amount of heat transfer from the warmed refrigerant. Additionally, the complexity of the swimming pool water heating systems taught in the aforementioned patents has elevated their cost of manufacture and rendered them uneconomical for residential or even limited commercial use.
There is therefore a need in the art to provide an inexpensive, easy to manufacture heating system for swimming pool water which utilizes the waste heat in the warmed refrigerant found in an air conditioning or refrigeration system. The swimming pool water heating system should be easy to install, easy to operate, long lasting and require little maintenance. Additionally, the heating system should provide a flow of water sufficient to allow an effective amount of heat transfer from the warmed refrigerant.